The reason is that measure allows the court to hear evidence that the accused committed prior sex-offenses, so the bill is meeting resistance in the House -- especially from one particular lawmaker.

There's universal agreement. Serial rapists belong in jail, but some avoid it because they managed to convince the court the sex was consensual.

"It came down to credibility," City State's Attorney Marilyn Mosby said.

Mosby helped convince a Senate committee to advance a bill that changes the law. The legislation will allow prosecutors to use the rapist's prior sex offenses as evidence at trial. Current law prohibits introducing someone's prior bad acts because it's considered prejudicial.

Baltimore County Sen. Jim Brochin is the bill sponsor.

"We have safe guards in there. First of all, you have to prove by clear and convincing evidence that the allegation occurred. Secondly, you have to tell the defense within 90 days, so they can prepare a counter. Thirdly, the probative value has to out-weigh the prejudicial value," Brockin said.

Although the bill is moving in the Senate, it's meeting stiff opposition by one person in the House. Judiciary Chairman Delegate Joe Vallario has the power to determine whether the legislation survives.

"If we work on it, we'll be working on the Senate bill, if we work on it," Vallario said. "There's a couple of reasons. Mostly prominently, the courts make those decisions on what comes in and what should not come in. It's very hard to think about legislating in that area."

Vallario is a defense attorney. He believes the Judicial Rules Committee should make the decision or it happens through case law.

"It's a pretty drastic step, a very drastic step because somebody is accused of a crime that happened on this day and they want to say, 'He had a bad act.' How much of that 'bad act' are you going to get into, especially when he was acquitted? That's a problem. Found guilty, no problem," Vallario said.